Optical communications technology is finding increasing use in a variety of applications. For example, optical communications links are being considered for replacement of wire interconnections between integrated circuits on a circuit board, and between circuit boards within electronic systems.
One component in an optical communication link is a transmitter for transmitting an optical beam onto a light detector. A challenge in an optical communication link is alignment between the transmitter and the detector to ensure that the optical beam illuminates the light detector. This challenge becomes more complex when a number of transmitters and detectors are used within the optical communication link. Misalignment can result in cross-talk between optical beams, and, in extreme cases, incorrect data being received by one or more of the detectors.
Maintaining proper alignment can be particularly difficult within an electronic system, as tolerances in the card cage holding the circuit boards can result in varying positions of the circuit boards relative to each other. In addition to static changes in relative position present during initial placement of cards into the card cage, dynamic variations in relative position can be introduced during operation due to heating, vibration, and other environmental effects.